European Journal of Cardiovascular Medicine

A congenital heart disease (CHD), also known as a congenital heart anomaly or congenital heart defect, is a defect in the structure of the heart or great vessels that is present at birth but more often diagnosed subsequently. The exact etiology of congenital heart defects is not fully understood yet. CHD is the most common major congenital anomaly and thus signifies a major global health problem (1). There has been a tremendous improvement in treatment of CHD. A significant proportion of patients born with CHD may lead a normal, productive life if diagnosed early and appropriate medical/surgical intervention is instituted. Thus, early detection of CHD and timely intervention are important for a better outcome in patients with congenital heart disease (2,3). Various imaging modalities are currently available including 2-dimensional Echocardiography, cardiac magnetic resonance imaging (MRI), and cardiac computed tomography (CT), all of which collectively provide invaluable information on cardiac anatomy and hemodynamics. Advanced imaging plays a role in diagnosis, pre-operative planning and determines the need and frequency of follow-up. The primary objective of this study was to study the spectrum of congenital heart diseases using 2-dimensional Echocardiography and cardiac CT in a tertiary care Centre of central Maharashtra region of India.

CHD may be diagnosed at virtually any age. Majority of conditions are usually discovered in neonatal period; other conditions are identified during infancy, childhood or sometimes in adult life (4). Cardiac CT is an important tool in the evaluation of congenital heart diseases. Cardiac CT can be used for accurate depiction of complex cardiovascular anatomic features. CT facilitates the assessment of extra-cardiac systemic and pulmonary arterial and venous structures. It is important for an operating surgeon to have extensive knowledge of cardiovascular anatomy, physiology, and surgical techniques (5). Compared with previous CT scans, newer 16-MDCT scanners yield images with better temporal and spatial resolution, greater anatomic coverage per rotation, more consistent enhancement with a need of lesser volume of intravascular contrast material, and higher-quality 2-dimensional reformation and 3-dimensional reconstruction owing to acquisition of an isotropic data set (6,7). Rapid imaging with these CT scanners requires less patient sedation than older-generation CT and conventional angiography (6,8). Although the role of CT in the evaluation of pediatric congenital heart diseases is being redefined and expanded, there are several generally accepted clinical indications for which the benefits of imaging outweigh the risks. Cardiac CT can be used to evaluate patients with congenital heart diseases known or suspected based on 2 dimensional echocardiographic findings for which further imaging is needed to characterize associated extra-cardiac anomalies before intervention. The pulmonary arteries, pulmonary veins, and aortic arch and great vessels may be inadequately characterized by 2-dimensional echocardiography, necessitating further assessment with CT. Cardiac CT can be used in the postoperative evaluation of congenital heart disease patients who have a variety of suspected treatment-related complications (9). Cardiac CT can also be useful before a reoperation to assess altered anatomic features related to previous surgery (9).

Diagnostic cardiac catheterization remains the gold standard for direct hemodynamic assessment in patients with congenital heart disease. Frequency of cardiac imaging varies by congenital heart disease subgroup, patient age, clinical status, surgical palliation, other cardiac interventions and residual hemodynamic anatomic defects (10,11). Invasive diagnostic cardiac catheterization studies should only be undertaken once other non-invasive imaging modalities have been used exhausted. It is then primarily required for hemodynamic assessment rather than imaging. Specific indications for invasive assessment remain the measurement of pulmonary vascular resistance, the evaluation of coronary arteries, and collateral vessels. Invasive assessment of systolic and end-diastolic ventricular function, pressure gradients, as well as shunts remains reserved for patients in whom non-invasive evaluation leaves uncertainty and the information is critical for clinical decision-making. Although diagnostic cardiac catheterization continues to be performed, many patients with simple congenital cardiac defects now undergo surgery based on non-invasive preoperative evaluation alone. Technical advances in 2-dimensional echocardiography, cardiac CT and MRI have been significant, and further advances will likely expand the roles of these techniques in the evaluation of congenital heart diseases and diminish the need for invasive diagnostic cardiac catheterization.

Eichhorn JG et al study found multidetector CT has high diagnostic accuracy, avoiding the need for additional techniques to plan the surgical approach (12). The diagnostic accuracy of CT is comparable to catheterization and is more accurate in detecting other complications that could put the patient's life at risk.
Khatri S et al suggested that 64-MDCT has many advantages over other conventional diagnostic techniques and that it provides key data concerning the surgical and interventional approach to adopt (13). Juan CC et al suggested that although 64-MDCT is good diagnostic technique in CHD, because of its lack of a therapeutic role it cannot replace catheterization (14).

A standard pretested validated proforma was used during the initial evaluation of every CHD patient who gets admitted to our hospital, which contained detailed history, sociodemographic data and clinical examination findings along with chest X-ray, ECG, and 2-dimensional Echocardiography findings. These data were used for this prospective observational study. The spectrum of congenital heart disease was then analyzed based on the age of presentation, gender distribution, and clinical presentation. All patients diagnosed with congenital heart disease were further evaluated by cardiac CT. The details of the study were recorded in a proforma, and the data were generated in an MS Excel sheet and analysis was done using the Statistical Package for the Social Sciences (SPSS).

Aim and Objective:
To study various types of simple & complex congenital heart diseases using 2-dimensional Echocardiography and Cardiac Computed Tomography (CT)
Study Design:
This was a Single Centre, Prospective Observational study.
Study Duration: The duration of this study was 36 months from the first enrollment.
Inclusion Criteria:
All age group patients with simple or complex congenital heart disease diagnosed by 2-Dimensional Echocardiography were further evaluated with cardiac CT who gave written & informed consent.
Exclusion Criteria:
1. Patients who had history of allergy to Intravenous iodinated contrast agent.
2. Patients with deranged renal function tests.
3. Patients with life threatening cardiac arrhythmias.
4. Pregnancy
The study was conducted in accordance with the approval and recommendations of institutional ethical board. Initially, written informed consent was obtained from all patients or parents in case of minor. Thereafter the individual details, clinical history & vital parameters were recorded. Thereafter 2-dimensional Echocardiography and Cardiac CT was carried out.
CT scanner used was a Siemens Somatom Perspective 128 Slice Scanner with the 0.48 s gantry rotation time and 64-slice data acquisition per gantry rotation results in acquisition of 100 slices per second.
Statistical analysis:
We did a single Centre prospective observational study. All patients with newly diagnosed CHD were evaluated initially with the help of 2D Echocardiography and later with cardiac CT for the three years duration from January 1, 2017 to December 31, 2019. The clinical, demographic, 2D Echocardiography and Cardiac CT details were retrieved, and descriptive analysis was done using the Statistical Package for the Social Sciences (SPSS). Quantitative data was presented with the help of Mean and Standard deviation. Comparison among the study group was done with the help of the unpaired t test as per results of normality test. A qualitative data was presented with the help of frequency and percentage table. Association among the study groups was assessed with the Fisher test, student ‘t’ test and Chi-Square test. ‘p’ value less than 0.05 was taken as significant.
Pearson's chi-squared test
Where Χ2 = Pearson's cumulative test statistic.
Oi = an observed frequency;
Ei = an expected frequency, asserted by the null hypothesis;
n = The number of cells in the table.
The following statistical significance tests would be applied:
1. T test was used to compare two independent groups of continuous data.
2. The “Chi square test” were used to compare categorical data.
3. Test of significance for difference of proportions “|Z|- Test”
4. For finding correlation coefficient “Karl Pearson Correlation Coefficient” was used.
5. 2×2 diagnostic table were used for calculating sensitivity, specificity, positive predictive value, negative predictive value, etc.
6. Finally, the calculated value was compared with the tabulated value at particular degree of freedom and find the level of significance. A “p-value” is considered non-significant if >0.05 and significant if < 0.05.
7. Results were graphically represented where deemed necessary.

8. Appropriate statistical software, including but not restricted to MS Excel, SPSS ver. 20 was used for statistical analysis. Graphical representation was done in MS Excel 2010.

Table 1- Mean Weight, Age and Heart Rate of congenital heart disease patients

The present Prospective Observational study was done on 40 patients at tertiary care Centre of Central Maharashtra Region of India to study the spectrum of congenital heart diseases using 2-dimensional echocardiography and Cardiac Computed Tomography (CT) to assess the morphological details of congenital heart diseases. The following observations were noted:
1. Mean weight of the study population was 42.77±26.867 kg, mean age was 15.7±12.04 years.
2.Mean heart rate was 94.1±16.04 bpm, range of heart rate was from 68 to 130 bpm.
3. Mean LVEF of study population was 59.6±2.7 % and mean contrast volume was 42.2±22.76 ml.
4. Mean flow rate was 3.85±0.802 ml/sec & mean scan time was 14.03±1.3 sec.
5. Male were more (57.5%) than female (42.5%) in our study. Ratio of male: female was 1.4:1
6. According to diagnosis TOF was present in 42.5% cases, while CoA was present in 12.5% cases.
7. ASD was present in 7.5% cases, POF was present in 7.5% cases, PDA was present in 7.5% cases, VSD was present in 5% cases.
8. Remaining diagnosis were Aorto-pulmonary window (2.5%), Double outlet right ventricle (5%), tricuspid atresia with univentricular heart 2.5%, TGA (2.5%), left isomerism (2.5%) and right isomerism (2.5%).
9. Associated anomalies of study population were Dextrocardia (5%), bicuspid aortic valve (5%), Coronary artery anomaly (2.5%), Absent left pulmonary artery (2.5%), PDA (2.5%), pulmonary atresia (2.5%), right sided aortic arch (2.5%), Isolated situs inversus (2.5%), Hemi-anomalous pulmonary venous drainage (2.5%) and Persistent Left SVC (2.5%).
10. Sedation was done in 32.5% cases; cardiac catheterization was done in 20% cases and cyanosis was present in 52.5% cases.
11. Significant association was present between cardiac catheterization and diagnosis. 4 cases with TOF, 2 cases with pentalogy of fallot, 1 case of right isomerism and 1 case of tricuspid atresia with univentricular heart required cardiac catheterization.
12. No significant association was found between associated anomaly and cardiac catheterization.
13. Significant association was found between cyanosis and requirement of cardiac catheterization. 6 cases had cyanosis who required cardiac catheterization.

The present prospective observational study was done on 40 patients at tertiary care Centre of Central Maharashtra, India to study the various congenital heart diseases using 2-dimensional Echocardiography and Cardiac Computed Tomography (CT).
In the present study, mean weight of the study population was 42.77±26.867 kg, mean age was 15.7±12.04 years, mean heart rate was 94.1±16.04 bpm and range of heart rate was from 68 to 130 bpm. The mean LVEF of study population was 59.6±2.7 % and mean contrast volume was 42.2±22.76 ml, mean flow rate was 3.85±0.802ml/sec & mean scan time was 14.03±1.3 sec. Male were more (57.5%) than female (42.5%) in our study. Ratio of male: female was 1.4:1. This is similar to the studies by Meshram RM et al (15). Meshram RM et al prospective, observational study assessing the prevalence and pattern of congenital heart disease (CHD) observed that CHD was more common in male (56.98%) giving rise to a male: female ratio was 1.3:1(15).
According to diagnosis in our study TOF was present in 42.5% cases, while CoA was present in 12.5% cases, ASD was present in 7.5% cases, PDA was present in 7.5% cases, POF was present in 7.5% cases, VSD was present in 5% cases. Remaining diagnosis were Aorto-pulmonary window (2.5%), Double outlet right ventricle (5%), Tricuspid atresia with univentricular heart (2.5%), TGA (2.5%), Left isomerism (2.5%) and Right isomerism (2.5%). This is comparable to the studies of Meshram RM et al (15), Zahid BS et al (16) and Marelli AJ et al (17). Meshram RM et al (15) prospective, observational study assessing the prevalence and pattern of congenital heart disease (CHD) found 287 (66.74%) patients were diagnosed with acyanotic type of CHD while 143 (33.26%) were cyanotic type. The most common CHD was VSD 129 (30.01%), followed by ASD 89 (20.70%), TOF 69 (16.05%), and PDA 44 (10.23%), respectively. The most common cyanotic CHD was TOF followed by transposition of great vessels, total anomalous pulmonary venous connection, and single ventricle. Zahid BS et al (16) study reported 52.8% acyanotic and 47.2% cyanotic congenital heart diseases, VSD (30.01%) was the most common CHD, followed by ASD (20.70%), TOF (16.05%), and PDA (10.23%). VSD was the most common acyanotic CHD while TOF was the most common cyanotic CHD.
Associated anomalies of present study population were Dextrocardia (5%), bicuspid aortic valve (5%), Absent left pulmonary artery (2.5%), Isolated situs inversus (2.5%), PDA (2.5%), pulmonary atresia (2.5%), Right sided aortic arch (2.5%), Coronary artery anomaly (2.5%), Persistent left SVC (2.5%) and Hemi-anomalous pulmonary venous drainage (2.5%). This is concordant to the studies of Meshram RM et al (15), Dabizzi RP et al (18), Aravind S et al (19), Saxena A et al (20) and Sedaghat F et al (21).
Aravind S et al (19) study reported extracardiac anomalies in 21.42% of patients. Saxena A et al (20) study reported a higher incidence of transposition of great vessels, single ventricle, total anomalous pulmonary venous connection, and double outlet right ventricle.
Sedaghat F et al (21) study determining the diagnostic value of CT in the cardiac anomalies reported non-cardiac abnormalities in the thoracic or abdominal organs including situs inversus / ambiguous (n=4) and aberrant right subclavian artery (n=2).
In our study, sedation was given in 32.5% cases, cardiac catheterization was done in 20% cases and cyanosis was present in 52.5% cases.
Bret-Zurita M et al observational retrospective cohort study analyzing the clinical application of 64-MDCT in pediatric CHD patients reported invasive diagnostic cardiac catheterization was performed in only 12.5% of patients. Of the patients studied, 90% had moderate to severe CHD and 80.2% had a level of complexity < 3 (level I). There were new findings in 77% of patients (82.9% with complex disease), which prompted a change in patient management in 35.6%.
In our study, no significant association was found between associated anomaly and cardiac catheterization. Greil GF et al67 noted similar observation in their study

Greil GF et al (22) observed Oblique reformatted images can be used to establish accurate measurements of the luminal diameter of the pulmonary artery that correlate highly with findings at cardiac catheterization.
Significant association was found between cyanotic congenital heart diseases and invasive diagnostic cardiac catheterization. 6 cases had cyanosis and required diagnostic cardiac catheterization. This finding was consistent with the study by O’Byrne ML et al (23).

The Tetralogy of Fallot (TOF) was the most common congenital heart defect, accounting for 42.5 % of all congenital heart disease cases. Cardiac CT accurately depicts simple and complex congenital cardiovascular anomalies, reduces need for invasive diagnostic cardiac catheterization and it is particularly valuable in the assessment of extra-cardiac vascular anomalies. CT provides complete evaluation of different anatomic structures, including the heart, pulmonary and systemic vasculature.

Conflict of Interest: There are no conflicts of interest to disclose.

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